Barrel pump



April 27, 1965 e. BOULET 3,180,275

BARREL PUMP Filed Feb. 20, 1963 4 Sheets-Sheet 1 INVENTOR GEORGES BOULFI' A ril 27, 1965 a. BOULET 3,180,275

BARREL PUMP Filed Feb. 20, 1963 4 Sheets-Sheet 2 INV BN1" OR GEORGES SOUL April 27, 1965 e. BOULET 3,180,275

BARREL PUMP Filed Feb. 20, 1963 4 Sheets-Sheet 3 GEORGES BOULET April 27, 1965 a. BOULET 3,1

BARREL PUMP Filed Feb. 20, 1963 4 Sheets-Sheet 4 INVENTOR GEORGES BOULE'T United States Patent "ice 3,180,275 BARREL PUMP Georges Boulet, Toulouse, Haute-Garonne, France, as-

signor to Socit a Responsabilit Limite: Recherches Etudes Production R.E.P., Paris, France, a corporation of France Filed Feb. 20, 1963, Ser. No. 259,897 Claims priority, application France, Feb. 21, 1962,

. 888,732 9 Claims. (Cl. 103-162) The present invention relates to barrel pumps having a distribution of the so-called slide-face type, in which pistons move in cylinders of the barrel having their axes parallel to the axis of rotation of the barrel. In pumps of this kind, the suction of the fluid into the cylinders and its delivery under pressure from the cylinders are effected through two ports formed in a plate or slideface perpendicular to the axis of the barrel, the said slide-face being in close frictional contact with a corresponding flat surface of the barrel.

In this surface are formed holes which each communicate with one of the cylinders; for each rotation of the barrel, they are successively superposed on one and on the other of the said ports. These ports are coupled respectively to a suction orifice and a delivery orifice of the pump. For each revolution of the barrel, there corresponds in each cylinder a suction stroke and a delivery stroke of its piston, which are respectively executed at the times during which the cylinder is in communication with the suction orifice and thenwith the delivery orifice.

The movement of the pistons is obtained, in well known manner, by means of a plate inclined to the axis of rotation, and against which rub swivel-jointed shoes on the extremity of each of the pistons opposite to the slide-face.

In these pumps, the pistons are subjected, due to the effect of the inclined plate, to oblique forces of which only the axial component is utilized, whereas the component perpendicular to the axis tends to produce wear of the surfaces of the pistons and the cylinders in frictional contact. For this reason, it has been considered necessary to give the pistons exaggerated lengths in order .to provide fairly long guiding surfaces for the said pistons with the object of limiting their wear. In addition, the pistons must be adjusted with a very small clearance so as to obtain good tightness.

This arrangement however involves in its turn a further drawback. The pistons, the mass of which then becomes large, are subjected to centrifugal forces. As these forces pass through the centers of gravity of the pistons, and as these centers of gravity are at each instant in a plane parallel to the inclined plate, the resultant of the forces is a couple which tends to tilt the barrel on its axis, and in consequence to interfere with the correct operation of the pump and to cause a bad support on the slide-face, resulting in premature wear of this slide-face and irregularities of fluid-tightness. V

One of the objects of the present invention is to provide a remedy for the double disadvantage which has been indicated above.

Independently of this result, the invention has also for an object to reduce the wear of the roller or journal bearings supporting the barrel, this wear resulting in a bad support of the barrel on the slide-face.

The main feature of the pump according to the invention consists in that the barrel is made-up of two portions arranged end to end, one driving the other in rotation; in that the pistons themselves are also formed in two parts arranged end to end, one constituting the pumping piston member proper and the other constituting a driving member for the piston members, interposed between the piston and the inclined plate; and in that coupling 3,l8h,275 Patented Apr. 27, 1965 means is provided between the two portions of the barrel on the one hand and between the two parts of the pistons on the other, such as to permit small movements in all directions between the driving members and the driven members.

By virtue of the invention, it is easy to obtain a perfectsupport of the barrel on its slide-face and perfect fluidtightness between the pumping piston member and its cylinder, since the piston is only subjected to very small lateral forces. Furthermore, the driving piston members need not be fitted with any great accuracy since they do not contribute to the fluid-tight sealing.-

Other characteristic features of the pump according to the invention will appear from the description which follows below, given by way of example and without implied limitation, of one form of embodiment shown in the figures of the accompanying drawings, in which:

FIG. 1 is an axial cross-section taken along the line II of FIG. 2.

FIG. 2 is an axial cross-section taken along the line II--II of FIG. 1.

FIG. 3 is a view of the slide-face in the direction of the arrows P of FIG. 1.

FIG. 4 is a view looking in the direction of the arrows F, of FIG. 1, showing the end of the driven barrel.

FIG. 5 is a view in the direction of the arrows P of FIG. 1, showing the opposite face of the driven barrel.

FIG. 6 is a view in the direction of the arrows F showing the end of the driving barrel.

FIG. 7 shows a detail of FIG. 2.

Referring first of all to FIGS. 1 and 2, the pump comprises a body formed by two cylyindrical parts 1 and 2, assembled together by bolts, and an end-piece 3 assembled to the body 1. The piece 3 comprises a suction chamber 4 with an inlet orifice 6 and a delivery chamber 5 with an outlet orifice 7.

In accordance with the invention, the barrel 8 which is driven by the driving shaft 9, is formed in two parts 8 8 The parts 8 or driving barrel, is assembled on the shaft 9 by means of longitudinal ribs on one of said parts, engaged in corresponding grooves in the other. The part 8 or driven barrel, is coupled to the driving barrel 8 by teeth 10 of the part 8 engaged in corresponding castellations of the part 8 (see FIGS. 4 and 6). The number of teeth and castellation is arbitrary; it could be reduced to three, two or even one only.

By virtue of this coupling, the barrel 8 is driven in rotation-about a ring 12 mounted in forced fit on the mandrel 13by the driving barrel 8 which rotates in turn on the mandrel 13 through the intermediary of a needlebearing 14. In the example shown, the mandrel 13 is provided with a flange 15 at one extremity for its fixation by bolts 15 to the end-piece 3. This construction is not the only one possible, and the mandrel 13 could for example belmade integral with the end-piece 3.

In accordance with the invention, a very small clearance is left between the teeth 10 and the corresponding castel-,

lations. This clearance, which ensures a coupling between the two barrels comparable to that of a cardan or universal joint, renders the driven barrel independent of all the movements which the driving barrel may make, with the exception of its movement ofrotation.

Within the barrels 8 and 8 are formed cylinders 17 and 17 in line with each other, in which are respectively movable a piston constituting a driving member 18 and a driven member 18 The members 18 and 13 of the pistons are coupled to each other by a crank-arm 19 provided with a double ball-and-socket joint. This coupling ensures that small angular and transverse movements of the driving barrel due to the force referred to above and tending to tilt the pistons are without effect on the piston 3 members 18 Each cylinder-piston unit constitutes a pumping unit. They are shown in this case as being nine in number, uniformly spaced around the axis of rotation of the barrel, but there may be any desired number of pumping units.

Each driving member 18 of each piston receives a thrust to cause the piston to be driven in its cylinder in known manner by means of a shoe 20 mounted on a ball joint 21. These shoes are driven by the rotation of the driving barrel 8 They are housed in the opening of an inclined plate 22, fitted on a ball joint 23 of the barrel 8,, the center of said joint being on the axis of the barrel. The inclined plate 22 is rotated, and its inclination is effected by the parallel plate 24 on which the shoes are in frictional contact. This plate is fixed, but its inclination is adjustable. It is provided, for that purpose, with trunnions 25 movable in rotation in the casing about the axis x-x (FIG. 2). The means for controlling the adjustment, which may be automatic or not, will not be described as it does not form part of the invention.

It will be noted that the shoes (20) are of a novel and original construction, which consists in the provision of a collar 20a on the edge of their opening. This collar has the effect of reinforcing the setting by increasing the inertia of the terminal section of the setting in the transverse sense. It can be formed by upsetting in compression or by setting in a press.

For every revolution of the barrel, each piston member 18 carries out a to-and-fro movement in its cylinder, successively pulled and pushed by the driving member 18 It sucks the liquid from the admission chamber 4 into the pumping chamber 25 of the cylinder Where the orifice 26 moves over the slide-face 27 along the admission port 28 which is in the shape of a circular arc (FIG. 3), and then delivers the liquid into the delivery chamber 5 when the orifice 26 moves along the arc-shaped delivery port 29.

It should be observed that, in a portion of its travel, one extremity of the driving member 18 penetrates into the cylinder 17 so that, if the member 18, and the driving member have the same diameter as is the case in the example shown the driving member should freely penetrate into cylinder 17 However, if the driving member 18 should have a diameter larger than that of the member 18 the driving member can come into abutment against the opening of the cylinder 17 The following precautions are therefore established. They consist either of providing the cylinder and the member 18, with a diameter greater than that of the driving member, or, as can be seen from FIGS. 1 and 2, in providing the cylinder in the portion into which the driving member 18 passes, a bore having a diameter greater than the diameter of this latter member. There is thus created an annular space 30 which can be utilized for housing a helicoidal spring 31 supported against the two parts of the barrel. It tends to push the main ball joint 23 and thereby the plate 22 and the shoes against the plate 24. This arrangement helps to return the pistons to their correct positions at the end of their suction stroke, to supplement the action of the main spring 32, which also pushes the driving barrel in the direction of the inclined plate.

The pump according to the invention also has the following remarkable features:

The passages 26 and also the passages 23 and 29 are flared outwards starting from the surface 27 of the slideface at which their junction is effected, and are connected by rounded portions with the internal faces of the walls of the chambers 25, 4 and 5 in which they are respectively constituted. This arrangement, which forms a kind of double venturi, has the effect of ensuring a uniform flow of fluid without turbulence, both at suction and at delivery.

The bearing surface of the driven barrel 8 on the slideface 27 is reduced by chamfers 33 and 34, which correctly limit the contact surface to that necessary to compensate the force due to the pressure on the bottoms of the cylinders.

In order to determine the size of the chamfers, it is assumed (FIG. 7) that the points a are at the admission pressure and the points b at the delivery pressure R. The resultant of the pressures is approximately the mean pressure defined by the surface of the triangles a, b, R applied to the surfaces indicated in dotted lines in FIG. 3. Grooves 35 and 36 in the form of circumferential arcs are formed in the surface of the slide-face so as to limit the surface thereof receiving the pressure and to collect the liquid which has infiltrated between the driven barrels and the slide-face, which has effected lubrication, said pressure arising as a result of the forces due to the pressure on the cylinder bottoms and of the forces due to the return springs of the pistons. These grooves communicate with radial grooves 37, from which the liquid flows into the annular space 38 (FIGS. 1 and 2) and returns to the reservoir or sump through the return orifice 39 of FIG. 1.

The lubrication of the friction surface of the slide-face 27 on the admission side, and the partial compensation of the effect of the central spring 32 and of the individual springs 31, when so required, are obtained in the following manner (see FIGS. 1 and 3).

Two oblique bores 40, opening at 41 on the surface of the slide-face 27, re-join oblique bores 42 opening into the arcuate groove 29 in which the delivery pressure exists. Through the conduit thus created, liquid under pressure reaches the orifice 41 and applies pressure on the barrel in the direction opposite to that which is produced by the axial spring 32 or the springs 31. The liquid escaping from these orifices lubricates the slide-face on the suction side (right-hand side of FIG. 3). The delivery side (left-hand side of FIG. 3) is sufficiently lubricated by the quantity of liquid under pressure which penetrates, as has been previously stated, from the delivery port 29 between the slide-face and the barrel. In the event that the pressure at the orifices 41 is too high, it may be reduced along the path of the liquid between the port 29 and the orifices 41.

Between the driving shaft 9 and the mandrel 13 is fitted a plug 45 provided with a joint 43, and which is held in position in the driving barrel by a tensioned elastic ring or circlip 44. The liquid which ensures the lubrication of the journal bearing 12 and of the needle bearing 14 cannot therefore escape between the driving shaft and the barrel.

The pump which has been described above may be modified in its construction without departing from the scope of the invention.

In addition, hydraulic motors of the same type as the pump described which conversely receive a liquid under pressure and which transform the energy received to a torque applied to a rotating shaft, also fall within the scope of the present invention. As a generic term for the motors and pump, the expression hydraulic engine is employed in the claims.

What I claim is:

1. A hydraulic engine of the rotary barrel type comprising a rotary barrel constituted of two members, means connecting said members of said barrel together in driving relationship for rotation while permitting slight universal movement between said members, said members defining a plurality of parallel cylinders each of which partially extends in each of the barrels, pistons slidably supported in each of the cylinders, include inclined plate means supported on one of the members of the barrel and coupled to the pistons to regulate movement of the pistons in the cylinders with rotary movement of the barrels, said pistons being constituted of two members in end to end relation supported in a respective member of the barrel, said pistons having spherical cavities in ends of each of the members thereof which face one another, and coupling means connecting said members of each of the pistons together for universal movement and comprising a crank arm including spherical end portions each accommodated in a respective spherical cavity of the piston members, said engine having fluid inlet and outlet ports adapted for being placed successively in communication with the cylinders in the other of the members of the barrel for the supply and discharge of fluid to the cylinders. V

2. An engine as claimed in claim 1 wherein said piston members which are in the cylinders in said other member of the barrel are supported in fluid tight relation therein while the piston members which are in the cylinders in said one member of the barrel are supported therein with clearance.

3. An engine as claimed in claim 1 wherein said means connecting said barrel members together comprises teeth on a first of the barrel members, the remaining barrel member having castellations accommodating. said teeth with slight clearance.

4. An engine as claimed in claim 2 wherein said other member of the barrel has a recess in each of the cylinders facing the piston member supported in said one barrel member to permit the free entry in said cylinders of the end of the latter piston member.

5. An engine as claimed in claim 4 comprising a helicoidal spring housed in the recesses urging the barrel members away from one another.

6. An engine as claimed in claim 1 wherein said ports are in the form of circular arcs, said cylinders having orifices which are successively in communication with the ports as the barrel undergoes rotation, said ports and orifices having in cross section smoothly curved surfaces which converge towards one another.

7. An engine as claimed in claim 1 wherein said engine comprises a body in which said ports are provided, the said other of the barrel members having surfaces in sliding contact with the body, said other barrel member having chamfers in said surface thereof which is in sliding contact with the body, said chamfers having a sufficient extent to limit the surface of said other barrel members to the area necessary to transmit tosaid body the force of the pistons against the other barrel members. 8. An engine as claimed in claim 7 in which grooves concentric with the ports are provided on the surface of the body in contact with the said other barrel member, said barrel forming a surrounding annular space with the body for collecting fluid which may pass between the surface of said other barrel member and said body, said body being provided with radial grooves opening into the first mentioned grooves for evacuating said fluid into said annular space, said body having an orifice for the discharge of fluid from said space.

9. An engine as claimed in claim 8 wherein fluid under high pressure is at one of the ports while fluid at low pressure is at the other of the ports, said body being provided with bores in communication with the port at which fluid under high pressure is present and opening into the surface of the body proximate the port at which the fiuid is at low'pressure to provide a conduit for the flow of fluid under pressure thereto between thev surface of the body and the surface of the barrel which slides on said body to provide lubrication thereat.

References (Iited by the Examiner UNITED STATES PATENTS 1,867,308 7/32 Durner 103-162 1,970,133 8/34 Ferris et a1. 103-162 2,769,393 11/56 Cardillo et al 103-462 X 2,987,006 6/61 Bowers et a1 103-462 3,092,036 6/ 63 Creighton 103-462 LAURENCE V. EFNER, Primary Examiner. 

1. A HYDRULIC ENGINE OF THE ROTARY BARREL TYPE COMPRISING A ROTARY BARREL CONSTITUTED OF TWO MEMBERS, MEANS CONNECTING SAID MEMBERS OF SAID BARREL TOGETHER IN DRIVING RELATIONSHIP FOR ROTATION WHILE PERMITTING SLIGHT UNIVERSAL MOVEMENT BETWEEN SAID MEMBERS, SAID MEMBERS DEFINING A PLURALITY OF PARALLEL CYLINDERS EACH OF WHICH PARTIALLY EXTENDS IN EACH OF THE BARRELS, PISTONS SLIDABLY SUPPORTED IN EACH OF THE CYLINDERS, INCLUDE INCLINED PLATE MEANS SUPPORTED ON ONE OF THE MEMBERS OF THE PLATE MEANS SUPPORTED ON ONE OF THE MEMBERS OF THE OF THE PISTONS IN THE CYLINDERS WITH ROTARY MOVEMENT OF THE BARRELS, SAID PISTONS BEING CONSTITUTED OF TWO MEMBERS IN END TO END RELATION SUPPORTED IN A RESPECTIVE 